There are multiple time lines, and the main character is currently in the wrong attractor field (where the bad ending always happens) and trying to get to the right one (where he is happy). Also, the main character of Yojouhan Shinwa Taikei sort-of gets Reading Steiner.

Jumps in the time where each creates a parallel world, where the protagonist is the great affected, but their relationships are not affected by this change. They still exist despite being parallel worlds.
The protagonist tries to reach his goal. In Tatami Galaxy this goal is simply to have a color pink life and in Steins;Gate, it is to stop an alleged conspiracy. The issue is how hard it is to get there by shedding their bucles or mental revelations.